Using ultrasound to research sudden cardiac arrest

From: Ultrasound.com

Toshiba America Medical Systems—manufacturer of the Aplio 500 CV and 300 CV cardiac ultrasound systems—has partnered with The Christ Hospital Health Network (Cincinnati, Ohio), The University of Mississippi Medical Center, and Cincinnati Children’s Hospital Medical Center in order to research the cause of sudden cardiac arrest.

According to lead investigator, Santosh Menon, MD, a cardiologist with the Christ Hospital Network, sudden cardiac arrest is the leading cause of death of high school–aged athletes. “SCD affects one to two out of every 100,000 young adults, and high school athletes participating in a vigorous sport have a two to three times greater risk,” said Menon.

In this study researchers used the Aplio 500 CV to conduct heart examinations on high school rowers who were competing in the US Rowing Youth National Championships at Melton Hill Lake in Oak Ridge, Tenn. in early June. Menon’s son is a competitive rower, which piqued his interest in this study population.

“What I realized is that they are the same size and the same height, and they all do the same sport year around, so it’s a very homogenous population,” Menon said. So, after doing some investigation, he decided to do the study.

According to the American Academy of Pediatrics, it is estimated that as many as 2,000 young adults under the age of 25 will die of sudden cardiac arrest each year, but Menon pointed out that current recommendations only include a physical exam for young athletes.

That doesn’t capture kids who may have risk factors for sudden cardiac death, such as ventricular wall thickness greater than a certain size, Menon said. “And the only way to figure that out is with an EKG (electrocardiogram) or echocardiogram.”

But even with these exams, said Menon, there can be false positives in which a young athlete may be ruled out of competition for an apparent abnormality. “We hope to identify what changes are considered normal for athletic hearts, versus the true presence of heart abnormalities, which may be the cause of SCD,” said Menon.

Working out of two rented trucks and with two Aplio 500 CV ultrasound systems, Menon, along with pediatric cardiologist Michelle Grenier, MD, examined between 50 and 60 athletes who volunteered to be studied at the youth rowing national championships

The Aplio 500 and Aplio 300 CV were launched just this past March at the American College of Cardiology annual meeting in San Francisco. According to Maher Elhihi, senior manager, market development for Toshiba ultrasound, these two systems “round off” Toshiba’s cardiac ultrasound offering. The Aplio 300 and 500 CV systems are 2D cardiovascular ultrasound systems that are “great systems for bread-and-butter 2D exams,” Elhihi said.

One of the tools featured on the Aplio cardiovascular ultrasound systems is Toshiba’s 2D Wall Motion Tracking technology, which provides users with superior visualization and quantitative analysis of myocardial wall motion.

Menon and Grenier examined each of the athletes between 6 and 12 hours after they had competed. Their vital signs were taken and they underwent EKGs and echocardiograms. Menon said that while they are still tabulating data (they want more time to look at the results using, for example, Doppler technology) a quick look at the EKGs and the echocardiograms allowed them to provide preliminary reports for each of the athletes and their parents.

“And we did find some abnormalities,” such as hypertrophic cardiomyopathy and even a case of Wolff-Parkinson-White syndrome, Menon said. “Some of these things needed to be addressed right away.”

The study so far "has told us a lot,” Menon said. “And it will help us define this population better [and tell us] what an athlete’s heart looks like under ultrasound at the high school level.”